This invention relates in general to an apparatus and a method for rolling compressible sheet material. More particularly, the invention relates to rolling fibrous sheets of insulation into a compressed roll. The method and apparatus are suitable for packing glass fiber insulation material.
Rolling sheets of insulation material into compressed rolls is well known. The prior art discloses or teaches machines for use in rolling sheet material. Such machines are commonly referred to as roll-up machines. Roll-up machines generally include a mandrel upon which the sheet material is rolled and one or more drive rollers for rolling the sheet material on the mandrel. To roll the sheet material on the mandrel, the sheet material is first fed between the drive rollers and the mandrel, then folded back around the mandrel, and subsequently tucked between the mandrel and the drive rollers. The sheet material is usually overlapped before it is tucked between the mandrel and the drive rollers to reduce the risk that the sheet material will wrinkle up at the core of the roll. This is commonly referred to as "crimping."
Currently, sheet material is manually tucked by machine operators who after tucking the sheet material must wrap the sheet material around the mandrel at least three times to sufficiently start the sheet material on the mandrel. Wide sheet materials are often difficult to tuck uniformly and wrap around the mandrel. If the machine operators are unable to tuck uniformly and start the sheet material, the sheet material may still wrinkle even if the sheet material is overlapped prior to being tucked and started. In an effort to solve this problem, a number of machine operators have been assigned the arduous task of manually tucking and starting the sheet material on the mandrel. However, this solution has not been entirely effective because the machine operators fail to tuck and start the sheet material uniformly relative to one another.
The sheet material not only has to be tucked uniformly and started, but constant uniform pressure must be applied on the sheet material as the sheet material is being rolled. This poses yet another problem. Conventional roll-up machines do not maintain a constant uniform pressure on the sheet material as the sheet material is being rolled on the mandrel. This results in an axial displacement of the core of the rolled sheet material relative to the outermost layers. The axial displacement of the core of the rolled sheet material is commonly referred to as "telescoping." A solution to this problem has yet to be presented.
In addition to being ineffective and labor intensive, manually tucking and starting sheet materials on the mandrel may pose risk of injury to the machine operators. This may be a safety concern to manufacturers and processors of sheet materials. A roll-up machine that will eliminate the need for manually tucking and starting sheet material on a mandrel is needed.